The road from this provincial capital to the Makassar Straits looks at first glance as if some ruthless timber baron had been at work alongside it.

Every few hundred yards, swatches of land have been stripped, the earth has been scorched and only a few spindly trees remain standing. The scene resembles Verdun after the battle.

The devastation is not, however, the handiwork of timber companies, but of farmers who have been doing what they have done for centuries -- "slashing and burning" the forest in preparation for planting rice and banana crops. Wherever the cleared patches appear, there are also huts with thatched roofs, lanudry on wash lines and men and women clad in sarongs minding children gossiping on porches or gathering kindling for cooking.

There is some disagreement among the experts as to the effect on the soil of this kind of agriculture in which the farmers move on to a new site after two years and return years later to repeat the cycle. Some say that after three or four cycles, the soil is so depleted that nothing will grow execpt elephant grass so tough not even jungle animals will eat it. Others point out that "slash and burn" agriculture has been praticed for centuries in the tropics without damaging the land unduly.

But there is no disagreement that the rapid spread of this kind of farming on Kalimantan, formerly Borneo, is now part of an environmental disaster in the making.

In the last few years, thousands of people, most from Sulawesi across the Makassar Straits, have been lured to Kalimantan by the prospect of jobs in the booming oil and timber business. Many have fanned out along the network of logging roads spreading deep into the interior and burned off thousands of acres.

Conservationists familiar with Kalimantan's forests express concern for the future of the region's wildlife, insects, plants and the fishing people who are the traditional inhabitants of the interior.

Kalimantan's problems are those of tropical hardwood forests all across the rainy equatorial belt of the world in the Amazon Basim in Brazil, West Africa, Malaysia and the Philippines.

According to the World Bank, the two billion acres of forest in developing countries is being used up at the rate of 50 to 60 million acres a year. At this rate, it contends, "current forest stock is likely to be consumed in less than 40 years, allowing for population growth in timber exports."

In Indonesia, there are an estimated 100 million acres of bare land that once were forested. In vast areas of New Guinea. Malaysia and the Philippines, grass has replaced trees. In Malaysia, commercial timber operations financed by overseas Chinese have stripped 1.4 million acres and slash and burn agriculture has cleared thousands more.

Future requirements for pulp for paper and wood for fuel are sure to increase the presures on the tropical timber supply. Some say 50 million acres will have to be replanted by the end of the century just to supply coming needs for firewood for the 1.5 billion people who still use trees as fuel for heat and cooking.

In a somber declaration at the end of the World Forest Congress in Jakarta in October the Congress warned of a "serious gap" between requirements for wood products and the capacity to satisfy them.

The needs of developed nations are primarly responsible for these new problems.

Between 1960 and 1975, developing countries increased their exports of wood products from $1.5 billion to $3 billion. Most of that wood ended up in developed countries, where wood supplies have tightened.

The shifting patterns of the timber trade are an example of the way the global pinch on resources affects everything from the environment to the strength of the dollar.

The depletion of the U.S.wood supply like the drawdown of U.S. oil reserves is one factor in the American trade balance.

Scarcity and rising prices of U.S. cedar and redwood means that the United States will have to import Indonesian wood for knotless interior paneling. In December, the Weyerhaeuser company of Toma. Wash., will begin exporting Indonesian lumber to the United States. This wood will substitute for cedar and redwood U.S. panelling.

American-based multinational timber companies return an undisclosed amount of dollars to the United State every year in the form of profits earned by their foreign subsidiaries. But this inflow of dollars in more than canceled out the outflow of capital to pay for timber investments and by imports of plywood, furniture and lumber from Korea and Taiwan.

The United States now buys about half of the wood exported by those, two countries and Korea and Taiwan buy raw logs from Kalimantan and other Southeast Asia wood for its construction industry is also a major beneficiary of the boom in timber operations in Kalimanten.

Thus, in dollar terms the major winners appear to be timber companies and Asian countries with strong economies. In timber, as in other commodities, developing countries have become a major resource base for developing nations.

The ecological impact of the timber boom in the tropics is apparent in South America and West Africa as well as in Asia.

Volkswagen has begun clearing 300,000 acres in northern Brazil for intgrated cattle grazing and beef slaughtering. The company has noted that the program can only be competed by "cutting and clearing the original vegetation."

Botanists also question the impact on the soil of Brazil of a $700 million forestry-mining-agriculture project covering 3.75 million acres of the Amazon jungle under the control of billionaire Daniel K. Ludwig. And officials at the Pentagon are worried by Silting resulting from logging that has begun to clog the Panama Canal.

Forestry experts say that in West Africa, the Ivory Coast "has sustained a level of destruction that cannot last for more than three or four more years."

Norman Myers, an internationally respected expert on tropical forests, wants governments to set aside at least one-fifth of all their forest reserves for the preservation of wildlife species, in the interest of science and medicine as well as of conservation.

"If a plant disappears that could cure cancer, there is no substitute," he says.

Many tropical plants do have medicinal properties, he says.

Enforcement of regulations aimed at protecting the forests tends to be lax, says John Blower of the World Wildlife Federation in Bogor, Indonesia. "You just don't meet foresters in these woods."

Here on Kalimantan, the devastation from shifting agriculture is closely related to timber operations.

The Dayak and Kutai people who are the traditional inhabitants of Kalimantan live mainly by fishing and hunting. They are river people, who dwell in huts built along the main streams and tributaries or in "long houses" occupied by as many as 100 people.

But government programs and the logging operations have changed the sociology and land use patterns of Kalimantan Government-sponsored "transmigration" programs have moved 6,000 people from overcrowded Java to eastern Kalimantan.

The government has been encouraging the settlers to engage in stable agriculture by planting paddy rice. But growing paddy rice is grueling work and the soil of Kalimantan is poor. Therefore, many have moved out along the logging roads to "slash and burn."

Meanwhile, others have come from Sulawesi, formerly the Celebes and have done the same.

"Unless the government does something we could lose 50 percent of this concession to slash and burn cultivators," an official of Weyerhaeuser said.

Although tropical forests seem lush and fertile, this often is a facade concealing underlying suit deficiencies. Botanists say that when the overhead canopy is removed, exposing the soil to tropical sun, oxidization takes place in the underlying iron, manganese, tin and bauxite that can turn the ground hard as a parking lot. The canopy's shade regulates the soil temperature, and the thick vegetation soaks up torrential downpours that otherwise would wash the soil away.

Timber company officials themselves acknowledge that fragile tropical soils are edpecially vulnerable to damage from compaction by heavy logging vehicles.

Wood unlike oil, is a renewable resource. South Korea, which had been stripped bare of trees 20 years ago is now dotted with pine trees as a result of an intensive government reforestation campaign.

But in the tropics, regeneration has turned out to be much more complicated than in temperate zones because of problems with insects, heavy rainfall and poor soil.

Wcyernaeuser in Indonesia and the Soriano timber-owing family in the Philippines are trying to find species adaptable to large-scale replanting, but Weyerhaeuser vice president Norman E. Johnson has acknowledged that there are political, economic and biologicai problems.

International attention has begun to focus on the problem. Eight countries bordering the Amazon basin have just signed a pact aimed at adopting conservation goals. A U.S. government task force has been set up to screen American-financed development projects to see that they do not harm forest environments.

Noting that forests can reduce wind erosion and slow the expansion of deserts as well as shelter wildlife, the World Bank has announced a new forestry policy that will stress rural development and replanting in forest areas instead of heavy commercial development of timber resources.